Question

A few differences between mitosis and meiosis have been given in the table below. Fill in the blanks using the options given.

$\begin{array}{ccc}& \text{Mitosis}& \text{Meiosis}\\ \text{Number of cell divisions}& 1& \text{(i)}\underset{–}{}\\ \text{Recombination of genetic material}& \text{(ii)}\underset{–}{}& \text{(iii)}\underset{–}{}\\ \text{Ploidy of the parent cell}& \text{2n}& \text{2n}\\ \text{Ploidy of the daughter cells}& \text{2n}& \text{(iv)}\underset{–}{}\end{array}$

• A. (i) - 2; (ii) - Absent; (iii) - Present; (iv) - 2n
• B. (i) - 1; (ii) - Present; (iii) - Present; (iv) - n
• C. (i) - 1; (i) Absent; (iii) - Present; (iv) - 2n
• D. (i) - 2; (ii) - Absent; (iii) - Present; (iv) - n

Answer 1

The correct option is D (i) - 2; (ii) - Absent; (iii) - Present; (iv) - n

Meiosis is a type of cell division that occurs in the reproductive cells of sexually reproducing organisms. This reduces the chromosome number by half, resulting in the formation of haploid daughter cells. Meiosis proceeds via two cycles of cell division. Since the parent cell has 2n (diploid) number of chromosomes, after meiosis the daughter cells will have only half the number of chromosomes and will have a ploidy of n. Recombination of genetic material is a characteristic feature of meiosis.

Mitosis is the type of cell division in which a parent cell divides once to give rise to identical daughter cells. Hence, the ploidy or the set of chromosomes is 2n in both the parent cell and the daughter cell. Recombination is not seen in mitosis.